Answer
$[59,95]$
Work Step by Step
Use the given information in the problem to create an inequality based on the original equation. Then multiply $\frac{9}{5}$, and add $32$ on all three sides to solve for $F$.
$C=\frac{5}{9}(F-32)$
$15\leq C\leq35$
$15\leq\frac{5}{9}(F-32)\leq35$
$27\leq(F-32)\leq63$
$59\leq F\leq95$
